Fall Arrest Device with Rope Drive Mechanism

Abstract

A combination of a drive mechanism associated with a fall arrest device. The drive mechanism includes a drive motor, a rope drive wheel, and a freewheel having a sleeve with axial recesses and clamping faces on an inner surface, which the clamping bodies are guided in a cage and are located in the recesses. The fall arrest device includes a drum onto which a safety rope is wound, a return spring configured to be tensioned during the unwinding of the safety rope from the drum, and a locking device configured to lock the drum against rotation in the safety rope in an unwinding direction in the event of a fall of a person carried by the safety rope.

What is claimed is: 
     
         1 . A combination of a drive mechanism associated with a fall arrest device, the combination comprising:
 the fall arrest device, having:
 a drum onto which a safety rope is wound; 
 a return spring configured to be tensioned during the unwinding of the safety rope from the drum; and 
 a locking device configured to lock the drum against rotation in the safety rope in an unwinding direction in the event of a fall of a person carried by the safety rope; 
   the drive mechanism, having:
 a drive motor; 
 a rope drive wheel; and 
 a freewheel having a sleeve with axial recesses and clamping faces on an inner surface, wherein clamping bodies are guided in a cage and are located in the recesses; 
   wherein the rope drive wheel is driven in a direction of rotation by the drive motor via the freewheel in order to drive the safety rope forward in one direction.   
     
     
         2 . The combination of  claim 1 , further comprising:
 a pressing wheel;   wherein the safety rope is passed through a gap between the drive wheel and the pressing wheel and in the gap is in frictional contact with the wheels.   
     
     
         3 . The combination of  claim 2 , further having an adjustable spring which presses against the pressing wheel. 
     
     
         4 . The combination of  claim 2  wherein the pressing wheel is rotatably mounted on a pivotable lever, and the lever is pretensioned by a spring force in order to press the pressing wheel against the safety rope. 
     
     
         5 . The combination of  claim 1 , wherein the drive motor is provided with a device for switching a motor speed between one direction of rotation and an opposite direction of rotation and for setting a predefined motor speed at least in the opposite direction of rotation in order to limit a movement speed of the rope in the opposite direction by virtue of the set predefined motor speed. 
     
     
         6 . The combination of  claim 5 , wherein the drive motor is a three-phase motor with a control circuit for switching a direction of rotation of the motor and for setting a predefined motor speed in both directions of rotation. 
     
     
         7 . The combination of  claim 6 , further comprising:
 a frequency inverter for setting the motor speed in both directions of rotation.   
     
     
         8 . The combination of  claim 1 , further comprising:
 a stop arranged below the drive wheel; and   a spacer attached to the safety rope in order to butt against the stop when the safety rope reaches an end position.   
     
     
         9 . The combination of  claim 8 , wherein the stop is a limit switch actuator. 
     
     
         10 . The combination of  claim 1 , wherein the drive motor can be controlled via radio or via a busbar. 
     
     
         11 . The combination of  claim 1 , wherein the freewheel is a component of the drive wheel and the drive wheel is mounted via the freewheel on a motor shaft or a shaft driven by the motor. 
     
     
         12 . The combination of  claim 1 , wherein the drive wheel has a rubber or plastic body, wherein the rubber or plastic body is arranged on the freewheel. 
     
     
         13 . The combination of  claim 2 , wherein the pressing wheel has a rubber or plastic body. 
     
     
         14 . The combination of  claim 1 , further comprising;
 a drive housing configured for attachment below the fall arrest device;   wherein both the drive wheel and the freewheel are disposed in the drive housing and the safety rope passes through the drive housing.   
     
     
         15 . The combination of  claim 8 , further comprising:
 a guide ring for the spacer carried on a housing of the drive mechanism.